At first glance I didn't think much of the 204Ruger. I thought, ok, so it can hit over
4,000fps velocity - so can a 22-250 with the right bullets/loads. But, then I began to look into the ballistics a little more, and a friend of mine got one. Dang, but it's a tack driving SOB! Very pleasant to shoot, accurate as all get out. Heck of a varmint cartridge!
As for a walking around varmint rifle you might want to check out Remington's light weight model, available in 204Ruger. I think it's the Model 700 LVSF - synthetic stock, with stainless action, stainless fluted 22" barrel.
The 204Ruger should have no problem with any varmints, including coyotes, but I'd draw the limit there. For deer I'd want something bigger. If you insist on a so-called dual purpose rifle, then go with a 243Winchester or a 25-06.

ps: Welcome to the forum.